1. Technical Field
The present invention relates to a conceptual network generating system that generates a conceptual network showing the conceptual relations between words, and a conceptual network generating method and a conceptual network generating program.
2. Related Art
A conceptual network shows conceptual connections (conceptual relations) existing between words that are systematically classified based on predetermined definitions. One type of conceptual relation is represented by the relation between an upper conception and a lower conception (“Is-a” relation). For example, in a case where the words such as “car” and “aircraft” are systematically classified under the category of “transportation”, the upper conception is “transportation” while the lower conception is “car” and “aircraft”. Conceptual relations are often shown in the form of an effective graph that is formed with nodes and links. For example, the conceptual relation between the upper conception “transportation” and the lower conception “car” is shown as “transportation→car”.
A conceptual network can be created by a semiautomatic operation in which some parts of analysis data are produced manually while the other parts are automatically produced with the use of a computer, and the produced data is checked by human eyes. However, this data producing operation requires human hands and large production costs, even though it is “semiautomatic”. Also, a conceptual network might be arbitrarily generated by a particular person in such an operation.
With the above facts being taken into consideration, there has been a demand for an automatic operation for generating conceptual networks.
However, by any conventional technique, the frequency information about the words contained in documents is used, and as a result, the conceptual relations between words cannot be accurately extracted.